Arizona motorists are paying less at the pump this week.

Officials with Triple-A Arizona said Thursday that the average statewide price for unleaded regular gasoline is $3.70 a gallon. That’s down by almost 4 cents from last week.

Triple-A officials say gasoline prices tend to start dropping in the fall with the trend continuing through late December.

This week’s national average is $3.79 per gallon, a decrease of nearly 5 cents from last week.

Tucson has the lowest average gasoline price in Arizona at $3.55 a gallon while Flagstaff has the highest at $3.89.

Mississippi and South Carolina both have the lowest average gas prices in the continental U.S. at $3.53 a gallon with California having the highest at $4.13 a gallon.